stair

Definitions

from The American Heritage® Dictionary of the English Language, 4th Edition

n. A series or flight of steps; a staircase. Often used in the plural.

n. One of a flight of steps.

from Wiktionary, Creative Commons Attribution/Share-Alike License

n. A single step in a staircase.

n. A series of steps, a staircase.

from the GNU version of the Collaborative International Dictionary of English

n. One step of a series for ascending or descending to a different level; -- commonly applied to those within a building.

n. A series of steps, as for passing from one story of a house to another; -- commonly used in the plural; but originally used in the singular only.

from The Century Dictionary and Cyclopedia

n. A step; a degree.

n. One of a series of steps to mount by: as, a flight of stairs.

n. A flight or succession of flights of steps, arranged one behind and above the other in such a way as to afford passage from a lower to a higher level, or vice versa: as, a winding stair; the back stair: often used in the plural in the same sense.

In this game of the Big Stair, the eye of the child can easily recognise an error, since if he mistakes, the stair is irregular, that is, there will be a high step, behind which the step which should have ascended, decreases.